So ... What Happened?

THE DINOSAUR perhaps never knew what hit him, or his planet. Or perhaps that is an exaggeration. Perhaps the big fellow did know that the sky had turned dark and the air had all this stuff in it.

We don't know what really occurred to wipe out the dinosaur back in that early dawning of history. But there are theories, and one is that the big fellow lost it when a huge asteroid or comet collided with Earth, blasting debris into the skies that eventually rained extinction upon his species.

That big-hit theory is now being buttressed by a new clue, no larger than a matchhead, which some scientists think could be a fragment of the supposed cataclysm that wiped out the dinosaurs.

Geophysicist Frank Kyte of the University of California at Los Angeles has found what he thinks might be the first known fragment of a gigantic, rocky asteroid that might have slammed into Earth 65 million years ago.

Chip probably did come from space

The fragment has been chemically analyzed as containing high concentrations of iridium, a rare metal, as well as iron, nickel and chromium at levels that are peculiar to extraterrestrial objects.

Other scientists also say the chemical analysis indicates that the chip probably did originate in space. Whether it actually came from the dinosaur-dooming asteroid remains a matter of debate.

The coarse-grained chip was retrieved from the floor of the Pacific Ocean as part of a thin layer of the planet's crust known as the K/T boundary. Scientists surmise that this layer was formed from the debris that fell back to Earth after being blown into the atmosphere by the asteroid.

Mr. Kyte says the fragment is the first object recovered from the K/T boundary "that is unarguably meteoric." He acknowledges that his personal interpretations concerning it are subject to further scrutiny.

The K/T asteroid is believed to have been about six miles wide, but its collision with Earth would have blasted it into pieces small enough to fit on the head of a pin. That occurrence is thought to have eliminated 70 percent of all plant and animal species, and, in the opinion of scientists, changed the course of evolution.

In the view of some scientists, the Kyte analysis reinforces the theory put forth in 1980 by geologist Walter Alvarez of the University of California at Berkeley. He postulated that the dinosaurs vanished after Earth was struck by a huge asteroid or comment.

Far a while, that theory seemed to be getting nowhere until, in 1989, scientists discovered evidence of a 180-mile-wide crater that had been gouged from the Earth on Mexico's Yucatan Peninsula.

We probably will never know for certain what happened back there, 65 million years ago, and that's too bad, considering how most of us tend to XXXdemand hard and fast answers about life.

It's a commentary on our times: Here we are, approaching the Millennium, wondering more and more what the future holds, and yet we have hardly a smidgen of firm knowledge about what happened in the past.

Perhaps we should stop worrying so much about "what happened?" and "what will happen?" After all, the answers, when you get right down to it, are beyond our puny control.